Light source module and display module

ABSTRACT

A light source module including a light guide plate and a light source is provided. The light guide plate has a light incident surface and a light emitting region, and the light guide plate has a plurality of grooves or protruding patterns thereon. The length of the grooves or the protruding patterns is smaller than the length of the light guide plate. The light source is disposed on the light incident surface of the light guide plate, and the grooves or the protruding patterns of the light guide plate are disposed beside the light incident surface.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the priority benefit of Taiwan applicationserial no. 98124889, filed Jul. 23, 2009. The entirety of theabove-mentioned patent application is hereby incorporated by referenceherein and made a part of specification.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention generally relates to a light source module and a displaymodule, and more particularly to a side incident type light sourcemodule and a display module having the side incident type light sourcemodule.

2. Description of Related Art

The main components of a liquid crystal display (LCD) apparatus includesan LCD panel and a backlight module, in which the LCD panel is formed bytwo substrates and a liquid crystal layer disposed between the twosubstrates, and the backlight module is used for providing the requiredlight source for the LCD apparatus to display images.

Typically, the backlight module is divided into a direct type and a sideincident type. The direct type backlight module is usually applied tolarge-sized LCDs, whereas the side incident type backlight module isusually adopted in small-sized LCDs.

FIG. 1 represents a schematic view illustrating a conventional sideincident type backlight module. Referring to FIG. 1, a conventional sideincident type backlight module 100 includes a light guide plate 110, alight source 120, an optical film set 130, and a reflector 140, in whichthe light source 120 is disposed on a side of the light guide plate 110,and the optical film set 130 and the reflector 140 are respectivelydisposed above and below the light guide plate 110. In order to improvethe brightness performance of the side incident type backlight module100, conventionally a light guide plate 110 having V-grooves is used.The V-grooves of the light guide plate 110 are disposed on an entirelight incident surface 110 a, meaning that the length of the of theV-grooves and the length of the light guide plate 110 are the same.After a light emitted from the light source 120 enters the light guideplate 110, the light is reflected by a reflector 140 on a bottom surface110 b of the light guide plate 110. By using the V-grooves to refractthe light, the front emitted luminance and the light source efficiencyare improved, thereby generating a planar light source having enhancedbrightness.

FIG. 2 represents a schematic view illustrating another conventionalside incident type backlight module. Referring to FIG. 2, a sideincident type backlight module 200 depicted in FIG. 2 is similar to theside incident type backlight module 100. The differences are: theV-grooves of a light guide plate 210 of the side incident type backlightmodule 200 depicted in FIG. 2 are disposed on an entire bottom surface210 b, the light emitted from a light source 220 enters the light guideplate 210, the light paths are guided directly upward by a reflector 240disposed beneath a bottom surface 210 b of the light guide plate 210,and the V-grooves are used for increasing the brightness of the frontemitted light.

It should be noted that whether the V-grooves are disposed on the lightemitting surface 110 a of the light guide plate 110 or disposed on thebottom surface 210 b of the light guide plate 210, when the sideincident type backlight modules 100 and 200 are assembled ortransported, the V-grooves may collide or cause friction with theoptical film set 130 disposed above the light guide plate 110 or thereflector 240 disposed below the light guide plate 210, thereby damagingthe V-grooves and forming a plurality of hot spots. Consequently, notonly is the display quality of the LCD apparatus compromised, theproduction costs are increased because extra optical films are needed tosolve the hot spot issue.

SUMMARY OF THE INVENTION

A light source module is provided, for reducing the hot spots generatedduring assembly or transport due to collisions of the light guide plate,thereby increasing yield and decreasing production costs.

A display module having a favorable display quality is also provided.

A light source module including a light guide plate and a light sourceis provided. The light guide plate has a light incident surface and alight emitting region, and the light guide plate has a plurality ofgrooves or a plurality of protruding patterns thereon, in which thelength of the grooves or the protruding patterns is smaller than thelength of the light guide plate. The light source is disposed on thelight incident surface of the light guide plate, and the grooves or theprotruding patterns of the light guide plate are disposed besides thelight incident surface.

A display module including a display panel and a light source module isprovided. The light source module is disposed on a side of the displaypanel, in which the light source module includes a light guide plate anda light source. The light guide plate has a light incident surface and alight emitting region, and the light guide plate has a plurality ofgrooves or a plurality of protruding patterns thereon, in which thelength of the grooves or the protruding patterns is smaller than thelength of the light guide plate. The light source is disposed on thelight incident surface of the light guide plate, and the grooves or theprotruding patterns of the light guide plate are disposed besides thelight incident surface.

In summary, since the length of the grooves or the protruding patternson the light guide plate is smaller than the length of the light guideplate, during assembly or transport of the light source module, thegrooves or the protruding patterns on the light guide plate can decreasethe area for which the light guide plate may collide or cause frictionwith other components (such as an optical film set disposed above thelight guide plate or a reflector disposed below the light guide plate).Consequently, the light source module can provide a more favorableplanar light source, thereby improving the display quality of thedisplay module, improving the yield of the light source module and thedisplay module, and decreasing production costs.

In order to make the aforementioned and other features and advantages ofthe invention more comprehensible, several embodiments accompanied withfigures are described in detail below.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are included to provide a furtherunderstanding of the invention, and are incorporated in and constitute apart of this specification. The drawings illustrate embodiments of theinvention and, together with the description, serve to explain theprinciples of the invention.

FIG. 1 represents a schematic view illustrating a conventional sideincident type backlight module.

FIG. 2 represents a schematic view illustrating another conventionalside incident type backlight module.

FIG. 3 represents a schematic diagram illustrating a display module inaccordance with one embodiment of the invention.

FIG. 4A represents a schematic side view of a backlight module of thedisplay module depicted in FIG. 3.

FIG. 4B represents a schematic top view of the light source moduledepicted in FIG. 4A.

FIG. 4C represents a schematic diagram illustrating a relationshipbetween the depth of the grooves on the light guide plate depicted inFIG. 4A and the length of the light emitting region.

FIG. 4D represents a schematic top view of the light guide plate inaccordance with another embodiment of the invention.

FIG. 5A represents a schematic side view of the light guide plate inaccordance with another embodiment of the invention.

FIG. 5B represents a schematic top view of the light guide platedepicted in FIG. 5A.

FIG. 6A represents a schematic side view of the light guide plate inaccordance with another embodiment of the invention.

FIG. 6B represents a schematic top view of the light guide platedepicted in FIG. 6A.

FIG. 6C represents a schematic diagram illustrating the relationshipbetween the depth of the grooves on the light guide plate depicted inFIG. 6A and the length of the light emitting region.

FIG. 7A represents a schematic side view of the light guide plate inaccordance with another embodiment of the invention.

FIG. 7B represents a schematic top view of the light guide platedepicted in FIG. 7A.

FIG. 8 represents a schematic side view of the light guide plate inaccordance with another embodiment of the invention.

FIG. 9 represents a schematic side view of the light guide plate inaccordance with another embodiment of the invention.

FIG. 10 represents a schematic top view of the light guide plate inaccordance with another embodiment of the invention.

DESCRIPTION OF EMBODIMENTS

FIG. 3 represents a schematic diagram illustrating a display module inaccordance with one embodiment of the invention. FIG. 4A represents aschematic side views of a backlight module of the display moduledepicted in FIG. 3. Referring concurrently to FIGS. 3 and 4A, a displaymodule 300 includes a display panel 400 and a light source module 500,in which the light source module 500 is disposed on a side of thedisplay panel 400, for example below the display panel 400. The lightsource module 500 includes a light guide plate 510 and a light source520. For example, the light source 520 can be a plurality of point lightsources disposed on at least one side of the light guide plate 510, andthe point light sources can be foinied by a plurality of light emittingdiodes (LEDs) for providing light. However, the invention is not limitedthereto. In other embodiments of the invention, the light source 520 canbe other types of light sources. Typically, light emitted from the lightsource 520 are guided by the light guide plate 510 and transmitted sothat the light source module 500 can provide a planar light sourcehaving for example, uniform brightness for use by the display panel 400.In the present embodiment of the invention, the light source module canbe a side incident type backlight module, and the display module can bea LCD module.

FIG. 4B represents a schematic top view of the light source moduledepicted in FIG. 4A. Referring concurrently to FIGS. 4A and 4B, thelight guide plate 510 is mainly used to convert the light source 520into a planar light source transmitting uniform light so that thedisplay panel 400 is provided with the required backlight module lightsource for display. In the present embodiment of the invention, thelight guide plate 510 has an upper surface 511 a, a lower surface 511 bcorresponding to the upper surface 511 a, a light incident surface 511c, a light emitting region 512 a, and a periphery region 512 b aroundthe light emitting region 512 a. The light guide plate 510 has aplurality of grooves 514 a˜514 f, and the length of the grooves 514a˜514 f is smaller than the length of the light guide plate 510. Morespecifically, the light emitting region 512 a has a length L, and thelengths of the grooves 514 a˜514 f in the light emitting region areD1˜D6, respectively. 0<D1˜D6<¼L is more preferable, although theinvention is not limited thereto. Additionally, the length of theperiphery region 512 b is A, and the lengths of the grooves are d1˜d6,respectively. A<d1˜d6<A+¼L is more preferable, although the invention isnot limited thereto. The light source 520 is disposed on a lightincident surface 511 c of the light guide plate 510, and the grooves 514a˜514 f of the light guide plate 510 are disposed besides the lightincident surface 511 c.

In the design of the light guide plate 510 according to the presentembodiment of the invention, the grooves 514 a˜514 f are disposed on theupper surface 511 a of the light guide plate 510. Moreover, the grooves514 a˜514 f are extending in a direction from the light incident surface511 c towards the light emitting region 512 a and across the peripheryregion 512 b. Additionally, since adjacent grooves of the grooves 514a˜514 f are connected to each other, there is no space between twoopposing sidewalls of the grooves 514 a˜514 f. The directions ofextension for the grooves 514 a˜514 f are parallel to each other, andthe lengths of the extensions are not all the same. Therefore, thelengths of the grooves 514 a˜514 f can be entirely different from eachother, as shown in FIG. 4B where the lengths d1˜d6 of the grooves 514a˜514 f are different from each other. Alternatively, the lengths of thegrooves 514 a˜514 f can be partially different, as shown in a lightguide plate 510 a depicted in FIG. 4D where the lengths d1′˜d3′ of thegrooves 514 a′˜514 c′ are different from each other, but the lengthsd4′˜d6′ of the grooves 514 d′˜514 f′ are the same. In other words, thelengths d4′˜d6′ of the grooves 514 d′˜514 f′ are not entirely the same.As shown in FIGS. 5A-5B, in another embodiment of the invention,adjacent grooves of the grooves 516 a˜516 d on a light guide plate 510 bcan also be disconnected from each other. That is to say, a spacingdistance exists between the sidewalls of the adjacent grooves 516 a˜516d. For example, the sidewalls of the grooves 516 a and 516 b are spacedapart from each other at a first distance a1, whereas the sidewalls ofthe grooves 516 c and 516 d are spaced apart from each other at a seconddistance a2, and the first distance a1 is substantially different fromthe second distance a2. It should be noted that in other embodiments ofthe invention undrawn in this description, the first distance a1 can besubstantially the same as the second distance a2.

FIG. 4C represents a schematic diagram illustrating a relationshipbetween the depth of the grooves on the light guide plate depicted inFIG. 4A and the length of the light emitting region. Referringconcurrently to FIGS. 4A˜4C, the depth (or the height) of the grooves514 a˜514 f in the light emitting region is shallower than the depth (orthe height) of the grooves 514 a˜514 f in the periphery region 512 b.The depth (or the height) of the grooves 514 a˜514 f decreases in alinear manner, therefore the depth (or the height) of the grooves 514a˜514 f decreases proportionally until smaller than ¼L at the lightemitting region 512 a (where L is the length of the light emittingregion 512 a). The longitudinal sections of the grooves 514 a˜514 f areV-shaped, for example, and the longitudinal sections of the grooves 514a˜514 f have the same angle α. As shown in FIGS. 6A-6C, in anotherembodiment of the invention, the depth (or height) of the grooves 517a˜517 f can also be decreasing in a nonlinear manner, meaning that thedepth (or height) of the grooves 517 a˜517 f is decreasing irregularly,and the depth (or height) of the grooves 517 a˜517 f is not decreasingproportionally from the periphery region 512 b towards the lightemitting region 512 a. In other words, the depth (or height) of thegrooves 517 a˜517 f can change in different manners. Moreover, inanother embodiment of the invention shown in FIGS. 7A and 7B, thelongitudinal section of a plurality of grooves 518 a˜518 f of a lightguide plate 510 d has at least one included angle, meaning that each setof two opposing sidewalls of the grooves 518 a˜518 f has a differenttilt angle. For example, the included angle between the two opposingsidewalls of the groove 518 a can be α1, and the included angle betweenthe two opposing sidewalls of the groove 518 b can be α2, in which theincluded angle α1 and the included angle α2 is different from eachother.

It should be noted that, embodiments of the invention are not limited bythe position or the type of the grooves 514 a˜514 f (or the grooves 514a′˜514 f′, the grooves 516 a˜516 d, the grooves 517 a˜517 f, the grooves518 a˜518 f) of the light guide plate 510 (or the light guide plates 510a˜510 d). Even though the grooves 514 a˜514 f (or the grooves 514 a′˜514f′, the grooves 516 a˜516 d, the grooves 517 a˜517 f, the grooves 518a˜518 f) are embodied to be disposed on of the upper surface 511 a oflight guide plate 510 (or the light guide plates 510 a˜510 d), and thelongitudinal sections of the grooves 514 a˜514 f (or the grooves 514a′˜514 f′, the grooves 516 a˜516 d, the grooves 517 a˜517 f, the grooves518 a˜518 f) are embodied to be V-shaped, in other embodiments of theinvention as shown in FIG. 8, the longitudinal sections of a pluralityof grooves 519 a˜519 f on a light guide plate 510 e can also beU-shaped. Furthermore, in other embodiments of the invention as shown inFIG. 9, the grooves 514′ on a light guide plate 510 f can be disposed ona lower surface 511 b, and these different designs are all technicalsolutions suitable for the invention and do not depart from the scope ofthe invention for which protection is sought.

Furthermore, referring again to FIG. 4A, the light source module 500 ofthe present embodiment of the invention further includes an optical filmset 530 and a reflector 540. The optical film set 530 is disposed abovethe light guide plate 510 for improving the distribution of the lightsource and allowing more uniformity of the emitted light. Typically, theoptical film set can include a prism sheet, a diffusion plate, acollecting sheet, a brightness enhanced film, a protection film, or acombination of the above-described optical films for furtheroptimization of the emitted light. The type and the number of theoptical film set 530 are varied in accordance with the actual demands,and embodiments of the invention do not place limits thereon. Thereflector 540, of a high reflectivity, is disposed under the light guideplate 510 and reflects the light from the light source 520 to improvethe efficiency of the light source 520.

This design of the grooves 514 a˜514 f (or the grooves 514 a′˜514 f′,the grooves 516 a˜516 d, the grooves 517 a˜517 f, the grooves 518 a˜518f, the grooves 519 a˜519 f) on the upper surface 511 a of the lightguide plate 510 (or the light guide plates 510 a˜510 e) can alleviatethe issue of conventional V-grooves having collisions or causingfriction with the optical film set 130 above the light guide plate 110and generating hot spots. Unlike conventional V-grooves having the samelength as the length of the light guide plate 110, in the presentembodiment of the invention, since the length of the grooves 514 a˜514 f(or the grooves 514 a′˜514 f′, the grooves 516 a˜516 d, the grooves 517a˜517 f, the grooves 518 a′˜518 f′, the grooves 519 a˜519 f) is smallerthan the length of the light guide plate 510 (or the light guide plates510 a˜510 e), when the light module 500 is being assembled ortransported, the grooves 514 a˜514 f (or the grooves 514 a′˜514 f′, thegrooves 516 a˜516 d, the grooves 517 a˜517 f, the grooves 518 a˜518 f,the grooves 519 a˜519 f) on the light guide plate 510 (or the lightguide plates 510 a˜510 e) can effectively reduce the area which cancollide or cause friction with the optical film set 530 disposed abovethe light guide plate 510. Consequently, the light source module 500 canprovide a better planar light source for improving the display qualityof the display module 300. Similarly, if the groove 514′ is disposed onthe lower surface 511 b of the groove 514′ as shown in FIG. 9, thenduring assembly or transportation of the light source module 500(referring to FIG. 4A), the groove 514′ can also effectively reduce thearea which can collide or cause friction with the reflector 540 belowthe light guide plate 510 f (referring to FIG. 4A). Consequently, thelight source module 500 can provide a better planar light source forimproving the display quality of the display module.

Moreover, in order to improve the brightness performance of the lightsource module 500, a sandblasting process can be performed on thesurfaces of the light guide plate 510 (or the light guide plates 510a˜510 e), which the grooves 514 a˜514 f (or the grooves 514 a′˜514 f′,the grooves 516 a˜516 d, the grooves 517 a˜517 f, the grooves 518 a˜518f, the grooves 519 a˜519 f, the groove 514′) are not formed thereon.Consequently, the lower surface 511 b of the light guide plate 510 (orthe light guide plates 510 a˜510 e) and the upper surface 511 a of thelight guide plate 510 f are both a surface have a plurality ofmicrostructures thereon. After the light emitted from the light source520 enters the light guide plate 510, the light is reflected by theuneven lower surface 511 b of the light guide plate 510 (or the lightguide plates 510 a˜510 e). By using the grooves 514 a˜514 f (or thegrooves 514 a′˜514 f′, the grooves 516 a˜516 d, the grooves 517 a˜517 f,the grooves 518 a˜518 f, the grooves 519 a˜519 f) to refract the light,and thus the light is made more uniform. Alternatively, the groove 514′on the lower surface 511 b of the light guide plate 510 f is used torefract the light, and thereby the light is made more uniform. Moreover,by using the uneven upper surface 511 a of the light guide plate 510 f,light can be more evenly distributed, thereby increasing the emittedluminance of the light emitting region and improving the efficiency ofthe light source. Hence, a planar light source having uniform brightnessis provided.

It should be noted that in other embodiments of the invention, as shownin FIG. 10, a light guide plate 510 g may also not have any grooves, butinstead the light guide plate 510 g can have a plurality of protrudingpatterns 515 a˜515 f. These protruding patterns 515 a˜515 f can bedisposed on the upper surface or the lower surface of the light guideplate 510 g, in which the length of the protruding patterns 515 a˜515 fis smaller than the length of the light guide plate 510 g. Asaforementioned in the previously described embodiments, in other undrawnembodiments of the invention, the length of the protruding patterns 515a˜515 f can be completely the same, completely different, or partiallythe same, the adjacent patterns can be connected to each other ordisconnected from each other, the depth or the height of theseprotruding patterns can be decreasing in a linear manner or in anirregular manner, the longitudinal section has at least one includedangle, as well as other characteristics. The light source 520 can bedisposed correspondingly on a side of the protruding patterns 515 a˜515f, or disposed on at least a side of the light guide plate 510 g (notdrawn in FIG. 10). A person of ordinary skill can arrive at thenecessary technical functions by referring to the above-describedembodiments and selecting the aforementioned components according topractical needs.

In embodiments of the invention, the light source 520 is disposed on oneside of the light guide plate 510. Other embodiments of the inventioncan dispose the light source 520 on the two opposing sides of the lightguide plate 510, where the grooves 514 a˜514 f (or the grooves 514a′˜514 f′, the grooves 516 a˜516 d, the grooves 517 a˜517 f, the grooves518 a˜518 f, the grooves 519 a˜519 f) or the protruding patterns 515a˜515 f are extending from the light incident surface 511 c of the lightguide plate 510 towards the light emitting region 512 a, correspondingto the light source 520.

Accordingly, embodiments of the invention provide designs of light guideplates for improving the issue of hot spots being generated duringassembly or transport of the light source module due to the light guideplate colliding or causing friction with the optical film set disposedthereabove or the reflector disposed therebelow. Consequently, thequality of the emitted light from the light source module is improved,and the display quality of the display module is enhanced. Moreover,since embodiments of the invention decrease the area for which the lightguide plate can collide or cause friction with the optical film set orthe reflector, the yield of the light source module is improved, therebyreducing production costs.

Although the invention has been described with reference to the aboveembodiments, it will be apparent to one of the ordinary skill in the artthat modifications to the described embodiment may be made withoutdeparting from the spirit of the invention. Accordingly, the scope ofthe invention will be defined by the attached claims not by the abovedetailed descriptions.

1. A light source module, comprising: a light guide plate having a lightincident surface and a light emitting region, the light guide platehaving a plurality of grooves or a plurality of protruding patternsthereon, wherein a length of the grooves or the protruding patterns issmaller than the length of the light guide plate; and a light sourcedisposed on the light incident surface of the light guide plate, and thegrooves or the protruding patterns of the light guide plate are disposedbeside the light incident surface.
 2. The light source module as claimedin claim 1, wherein the light guide plate has an upper surface and alower surface, and the grooves or the protruding patterns are disposedin at least one of the upper surface or the lower surface.
 3. The lightsource module as claimed in claim 2, wherein the grooves or theprotruding patterns are disposed in one of the upper surface or thelower surface of the light guide plate, and another surface of the uppersurface and the lower surface is a surface having a plurality ofmicrostructures.
 4. The light source module as claimed in claim 2,wherein the light emitting region has a length L, the length of thegrooves or the protruding patterns in the light emitting region is D,and 0<D<¼L.
 5. The light source module as claimed in claim 2, whereinthe light guide plate further comprises a periphery region around thelight emitting region, and the grooves or the protruding patterns areextending from the light incident surface towards the light emittingregion across the periphery region.
 6. The light source module asclaimed in claim 5, wherein the length of the periphery region is A, thelength of the grooves is d, and A<d<A+¼L.
 7. The light source module asclaimed in claim 2, wherein a depth or a height of the grooves or theprotruding patterns in the periphery region is larger than the depth orthe height of the grooves or the protruding patterns in the lightemitting region.
 8. The light source module as claimed in claim 7,wherein the depth or the height of the grooves or the protrudingpatterns decreases in a linear manner.
 9. The light source module asclaimed in claim 7, wherein the depth or the height of the grooves orthe protruding patterns decreases in a nonlinear manner.
 10. The lightsource module as claimed in claim 1, wherein the depth or the height ofthe grooves or the protruding patterns changes in different manners. 11.The light source module as claimed in claim 1, wherein the lengths ofthe grooves or the protruding patterns are not entirely the same. 12.The light source module as claimed in claim 1, wherein the longitudinalsections of the grooves or the protruding patterns are V-shaped orU-shaped.
 13. The light source module as claimed in claim 12, whereinthe longitudinal sections of the grooves or the protruding patterns haveat least one included angle.
 14. The light source as claimed in claim 1,wherein the adjacent grooves or protruding patterns are connected toeach other.
 15. The light source as claimed in claim 1, wherein theadjacent grooves or protruding patterns are not connected to each other.16. The light source as claimed in claim 1, wherein the extendingdirections of the grooves or the protruding patterns are parallel toeach other.
 17. The light source module as claimed in claim 1, furthercomprising an optical film set disposed above the upper surface of thelight guide plate.
 18. A display module, comprising: a display panel;and a light source module as claimed in claim 1, disposed on a side ofthe display panel.